Personalizing Chemotherapy with MRI and Ultrasound

New ultrasound technology provides more rapid evidence of how a tumour responds to therapy

What if an ultrasound could detect if a patient’s cancer treatment was working after just one week of therapy?

Using quantitative ultrasound and magnetic resonance imaging (MRI), Dr. Gregory Czarnota and his team are working to make “personalized chemotherapy” a reality for patients with advanced breast cancer at Toronto’s Sunnybrook Health Sciences Centre.

“We’ve recently been able to demonstrate within a week of somebody starting their chemotherapy what the ultimate outcome is going to be six months later,” said Dr. Czarnota. “We know whether the tumour is going to potentially respond, or whether it’s not responding to that particular chemotherapy.”

Around one in nine women will be diagnosed with breast cancer at some point in their lives. Patients typically receive “one-size-fits-all” chemotherapy treatments that are only effective for a certain percentage of the population, he remarks.

Computed tomography (CT) scans are used currently to measure the change in tumour size, but are typically only done many months post treatment. For patients with advanced breast cancer, this might be too late.

Dr. Czarnota’s team uses a specialized form of ultrasound, extracting image biomarkers that detect cell death. When tumour cells die, they have properties that sound different from ultrasound and also look different in a magnetic field. These changes can be detected just hours after a patient begins chemotherapy or radiation.

“We’re tracking whether or not a patient’s chemotherapy is having its intended effect,” said Dr. Czarnota. “The goal is that if someone is receiving an ineffective drug, to switch it to one that is effective – or even a different type of therapy that is effective.”

Breast cancer has been the focus of the team’s research thus far, says Dr. Czarnota, but the approach, in principle, will work on any cancer that can be imaged with an ultrasound.

A randomized clinical trial has been underway at Sunnybrook since January 2015. Patients receive either conventional therapy, or quantitative ultrasound will be used “to deliver personalized medicine this way for the first time ever”.

“We’re at the stage now where we’ve put in 20 years of work,” said Dr. Czarnota. “I really think this technology stands to change the way that things are done in the medical field in short order.”